xref: /llvm-project/llvm/lib/Target/PowerPC/PPCTargetTransformInfo.cpp (revision f026812110878484d003f18660492e9321ef2df1)
1 //===-- PPCTargetTransformInfo.cpp - PPC specific TTI ---------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "PPCTargetTransformInfo.h"
10 #include "llvm/Analysis/CodeMetrics.h"
11 #include "llvm/Analysis/TargetLibraryInfo.h"
12 #include "llvm/Analysis/TargetTransformInfo.h"
13 #include "llvm/CodeGen/BasicTTIImpl.h"
14 #include "llvm/CodeGen/CostTable.h"
15 #include "llvm/CodeGen/TargetLowering.h"
16 #include "llvm/CodeGen/TargetSchedule.h"
17 #include "llvm/IR/IntrinsicsPowerPC.h"
18 #include "llvm/Support/CommandLine.h"
19 #include "llvm/Support/Debug.h"
20 #include "llvm/Support/KnownBits.h"
21 #include "llvm/Transforms/InstCombine/InstCombiner.h"
22 #include "llvm/Transforms/Utils/Local.h"
23 
24 using namespace llvm;
25 
26 #define DEBUG_TYPE "ppctti"
27 
28 static cl::opt<bool> DisablePPCConstHoist("disable-ppc-constant-hoisting",
29 cl::desc("disable constant hoisting on PPC"), cl::init(false), cl::Hidden);
30 
31 // This is currently only used for the data prefetch pass
32 static cl::opt<unsigned>
33 CacheLineSize("ppc-loop-prefetch-cache-line", cl::Hidden, cl::init(64),
34               cl::desc("The loop prefetch cache line size"));
35 
36 static cl::opt<bool>
37 EnablePPCColdCC("ppc-enable-coldcc", cl::Hidden, cl::init(false),
38                 cl::desc("Enable using coldcc calling conv for cold "
39                          "internal functions"));
40 
41 static cl::opt<bool>
42 LsrNoInsnsCost("ppc-lsr-no-insns-cost", cl::Hidden, cl::init(false),
43                cl::desc("Do not add instruction count to lsr cost model"));
44 
45 // The latency of mtctr is only justified if there are more than 4
46 // comparisons that will be removed as a result.
47 static cl::opt<unsigned>
48 SmallCTRLoopThreshold("min-ctr-loop-threshold", cl::init(4), cl::Hidden,
49                       cl::desc("Loops with a constant trip count smaller than "
50                                "this value will not use the count register."));
51 
52 //===----------------------------------------------------------------------===//
53 //
54 // PPC cost model.
55 //
56 //===----------------------------------------------------------------------===//
57 
58 TargetTransformInfo::PopcntSupportKind
59 PPCTTIImpl::getPopcntSupport(unsigned TyWidth) {
60   assert(isPowerOf2_32(TyWidth) && "Ty width must be power of 2");
61   if (ST->hasPOPCNTD() != PPCSubtarget::POPCNTD_Unavailable && TyWidth <= 64)
62     return ST->hasPOPCNTD() == PPCSubtarget::POPCNTD_Slow ?
63              TTI::PSK_SlowHardware : TTI::PSK_FastHardware;
64   return TTI::PSK_Software;
65 }
66 
67 Optional<Instruction *>
68 PPCTTIImpl::instCombineIntrinsic(InstCombiner &IC, IntrinsicInst &II) const {
69   Intrinsic::ID IID = II.getIntrinsicID();
70   switch (IID) {
71   default:
72     break;
73   case Intrinsic::ppc_altivec_lvx:
74   case Intrinsic::ppc_altivec_lvxl:
75     // Turn PPC lvx -> load if the pointer is known aligned.
76     if (getOrEnforceKnownAlignment(
77             II.getArgOperand(0), Align(16), IC.getDataLayout(), &II,
78             &IC.getAssumptionCache(), &IC.getDominatorTree()) >= 16) {
79       Value *Ptr = IC.Builder.CreateBitCast(
80           II.getArgOperand(0), PointerType::getUnqual(II.getType()));
81       return new LoadInst(II.getType(), Ptr, "", false, Align(16));
82     }
83     break;
84   case Intrinsic::ppc_vsx_lxvw4x:
85   case Intrinsic::ppc_vsx_lxvd2x: {
86     // Turn PPC VSX loads into normal loads.
87     Value *Ptr = IC.Builder.CreateBitCast(II.getArgOperand(0),
88                                           PointerType::getUnqual(II.getType()));
89     return new LoadInst(II.getType(), Ptr, Twine(""), false, Align(1));
90   }
91   case Intrinsic::ppc_altivec_stvx:
92   case Intrinsic::ppc_altivec_stvxl:
93     // Turn stvx -> store if the pointer is known aligned.
94     if (getOrEnforceKnownAlignment(
95             II.getArgOperand(1), Align(16), IC.getDataLayout(), &II,
96             &IC.getAssumptionCache(), &IC.getDominatorTree()) >= 16) {
97       Type *OpPtrTy = PointerType::getUnqual(II.getArgOperand(0)->getType());
98       Value *Ptr = IC.Builder.CreateBitCast(II.getArgOperand(1), OpPtrTy);
99       return new StoreInst(II.getArgOperand(0), Ptr, false, Align(16));
100     }
101     break;
102   case Intrinsic::ppc_vsx_stxvw4x:
103   case Intrinsic::ppc_vsx_stxvd2x: {
104     // Turn PPC VSX stores into normal stores.
105     Type *OpPtrTy = PointerType::getUnqual(II.getArgOperand(0)->getType());
106     Value *Ptr = IC.Builder.CreateBitCast(II.getArgOperand(1), OpPtrTy);
107     return new StoreInst(II.getArgOperand(0), Ptr, false, Align(1));
108   }
109   case Intrinsic::ppc_altivec_vperm:
110     // Turn vperm(V1,V2,mask) -> shuffle(V1,V2,mask) if mask is a constant.
111     // Note that ppc_altivec_vperm has a big-endian bias, so when creating
112     // a vectorshuffle for little endian, we must undo the transformation
113     // performed on vec_perm in altivec.h.  That is, we must complement
114     // the permutation mask with respect to 31 and reverse the order of
115     // V1 and V2.
116     if (Constant *Mask = dyn_cast<Constant>(II.getArgOperand(2))) {
117       assert(cast<FixedVectorType>(Mask->getType())->getNumElements() == 16 &&
118              "Bad type for intrinsic!");
119 
120       // Check that all of the elements are integer constants or undefs.
121       bool AllEltsOk = true;
122       for (unsigned i = 0; i != 16; ++i) {
123         Constant *Elt = Mask->getAggregateElement(i);
124         if (!Elt || !(isa<ConstantInt>(Elt) || isa<UndefValue>(Elt))) {
125           AllEltsOk = false;
126           break;
127         }
128       }
129 
130       if (AllEltsOk) {
131         // Cast the input vectors to byte vectors.
132         Value *Op0 =
133             IC.Builder.CreateBitCast(II.getArgOperand(0), Mask->getType());
134         Value *Op1 =
135             IC.Builder.CreateBitCast(II.getArgOperand(1), Mask->getType());
136         Value *Result = UndefValue::get(Op0->getType());
137 
138         // Only extract each element once.
139         Value *ExtractedElts[32];
140         memset(ExtractedElts, 0, sizeof(ExtractedElts));
141 
142         for (unsigned i = 0; i != 16; ++i) {
143           if (isa<UndefValue>(Mask->getAggregateElement(i)))
144             continue;
145           unsigned Idx =
146               cast<ConstantInt>(Mask->getAggregateElement(i))->getZExtValue();
147           Idx &= 31; // Match the hardware behavior.
148           if (DL.isLittleEndian())
149             Idx = 31 - Idx;
150 
151           if (!ExtractedElts[Idx]) {
152             Value *Op0ToUse = (DL.isLittleEndian()) ? Op1 : Op0;
153             Value *Op1ToUse = (DL.isLittleEndian()) ? Op0 : Op1;
154             ExtractedElts[Idx] = IC.Builder.CreateExtractElement(
155                 Idx < 16 ? Op0ToUse : Op1ToUse, IC.Builder.getInt32(Idx & 15));
156           }
157 
158           // Insert this value into the result vector.
159           Result = IC.Builder.CreateInsertElement(Result, ExtractedElts[Idx],
160                                                   IC.Builder.getInt32(i));
161         }
162         return CastInst::Create(Instruction::BitCast, Result, II.getType());
163       }
164     }
165     break;
166   }
167   return None;
168 }
169 
170 int PPCTTIImpl::getIntImmCost(const APInt &Imm, Type *Ty,
171                               TTI::TargetCostKind CostKind) {
172   if (DisablePPCConstHoist)
173     return BaseT::getIntImmCost(Imm, Ty, CostKind);
174 
175   assert(Ty->isIntegerTy());
176 
177   unsigned BitSize = Ty->getPrimitiveSizeInBits();
178   if (BitSize == 0)
179     return ~0U;
180 
181   if (Imm == 0)
182     return TTI::TCC_Free;
183 
184   if (Imm.getBitWidth() <= 64) {
185     if (isInt<16>(Imm.getSExtValue()))
186       return TTI::TCC_Basic;
187 
188     if (isInt<32>(Imm.getSExtValue())) {
189       // A constant that can be materialized using lis.
190       if ((Imm.getZExtValue() & 0xFFFF) == 0)
191         return TTI::TCC_Basic;
192 
193       return 2 * TTI::TCC_Basic;
194     }
195   }
196 
197   return 4 * TTI::TCC_Basic;
198 }
199 
200 int PPCTTIImpl::getIntImmCostIntrin(Intrinsic::ID IID, unsigned Idx,
201                                     const APInt &Imm, Type *Ty,
202                                     TTI::TargetCostKind CostKind) {
203   if (DisablePPCConstHoist)
204     return BaseT::getIntImmCostIntrin(IID, Idx, Imm, Ty, CostKind);
205 
206   assert(Ty->isIntegerTy());
207 
208   unsigned BitSize = Ty->getPrimitiveSizeInBits();
209   if (BitSize == 0)
210     return ~0U;
211 
212   switch (IID) {
213   default:
214     return TTI::TCC_Free;
215   case Intrinsic::sadd_with_overflow:
216   case Intrinsic::uadd_with_overflow:
217   case Intrinsic::ssub_with_overflow:
218   case Intrinsic::usub_with_overflow:
219     if ((Idx == 1) && Imm.getBitWidth() <= 64 && isInt<16>(Imm.getSExtValue()))
220       return TTI::TCC_Free;
221     break;
222   case Intrinsic::experimental_stackmap:
223     if ((Idx < 2) || (Imm.getBitWidth() <= 64 && isInt<64>(Imm.getSExtValue())))
224       return TTI::TCC_Free;
225     break;
226   case Intrinsic::experimental_patchpoint_void:
227   case Intrinsic::experimental_patchpoint_i64:
228     if ((Idx < 4) || (Imm.getBitWidth() <= 64 && isInt<64>(Imm.getSExtValue())))
229       return TTI::TCC_Free;
230     break;
231   }
232   return PPCTTIImpl::getIntImmCost(Imm, Ty, CostKind);
233 }
234 
235 int PPCTTIImpl::getIntImmCostInst(unsigned Opcode, unsigned Idx,
236                                   const APInt &Imm, Type *Ty,
237                                   TTI::TargetCostKind CostKind) {
238   if (DisablePPCConstHoist)
239     return BaseT::getIntImmCostInst(Opcode, Idx, Imm, Ty, CostKind);
240 
241   assert(Ty->isIntegerTy());
242 
243   unsigned BitSize = Ty->getPrimitiveSizeInBits();
244   if (BitSize == 0)
245     return ~0U;
246 
247   unsigned ImmIdx = ~0U;
248   bool ShiftedFree = false, RunFree = false, UnsignedFree = false,
249        ZeroFree = false;
250   switch (Opcode) {
251   default:
252     return TTI::TCC_Free;
253   case Instruction::GetElementPtr:
254     // Always hoist the base address of a GetElementPtr. This prevents the
255     // creation of new constants for every base constant that gets constant
256     // folded with the offset.
257     if (Idx == 0)
258       return 2 * TTI::TCC_Basic;
259     return TTI::TCC_Free;
260   case Instruction::And:
261     RunFree = true; // (for the rotate-and-mask instructions)
262     LLVM_FALLTHROUGH;
263   case Instruction::Add:
264   case Instruction::Or:
265   case Instruction::Xor:
266     ShiftedFree = true;
267     LLVM_FALLTHROUGH;
268   case Instruction::Sub:
269   case Instruction::Mul:
270   case Instruction::Shl:
271   case Instruction::LShr:
272   case Instruction::AShr:
273     ImmIdx = 1;
274     break;
275   case Instruction::ICmp:
276     UnsignedFree = true;
277     ImmIdx = 1;
278     // Zero comparisons can use record-form instructions.
279     LLVM_FALLTHROUGH;
280   case Instruction::Select:
281     ZeroFree = true;
282     break;
283   case Instruction::PHI:
284   case Instruction::Call:
285   case Instruction::Ret:
286   case Instruction::Load:
287   case Instruction::Store:
288     break;
289   }
290 
291   if (ZeroFree && Imm == 0)
292     return TTI::TCC_Free;
293 
294   if (Idx == ImmIdx && Imm.getBitWidth() <= 64) {
295     if (isInt<16>(Imm.getSExtValue()))
296       return TTI::TCC_Free;
297 
298     if (RunFree) {
299       if (Imm.getBitWidth() <= 32 &&
300           (isShiftedMask_32(Imm.getZExtValue()) ||
301            isShiftedMask_32(~Imm.getZExtValue())))
302         return TTI::TCC_Free;
303 
304       if (ST->isPPC64() &&
305           (isShiftedMask_64(Imm.getZExtValue()) ||
306            isShiftedMask_64(~Imm.getZExtValue())))
307         return TTI::TCC_Free;
308     }
309 
310     if (UnsignedFree && isUInt<16>(Imm.getZExtValue()))
311       return TTI::TCC_Free;
312 
313     if (ShiftedFree && (Imm.getZExtValue() & 0xFFFF) == 0)
314       return TTI::TCC_Free;
315   }
316 
317   return PPCTTIImpl::getIntImmCost(Imm, Ty, CostKind);
318 }
319 
320 unsigned
321 PPCTTIImpl::getUserCost(const User *U, ArrayRef<const Value *> Operands,
322                         TTI::TargetCostKind CostKind) {
323   // We already implement getCastInstrCost and getMemoryOpCost where we perform
324   // the vector adjustment there.
325   if (isa<CastInst>(U) || isa<LoadInst>(U) || isa<StoreInst>(U))
326     return BaseT::getUserCost(U, Operands, CostKind);
327 
328   if (U->getType()->isVectorTy()) {
329     // Instructions that need to be split should cost more.
330     std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, U->getType());
331     return LT.first * BaseT::getUserCost(U, Operands, CostKind);
332   }
333 
334   return BaseT::getUserCost(U, Operands, CostKind);
335 }
336 
337 bool PPCTTIImpl::mightUseCTR(BasicBlock *BB, TargetLibraryInfo *LibInfo,
338                              SmallPtrSetImpl<const Value *> &Visited) {
339   const PPCTargetMachine &TM = ST->getTargetMachine();
340 
341   // Loop through the inline asm constraints and look for something that
342   // clobbers ctr.
343   auto asmClobbersCTR = [](InlineAsm *IA) {
344     InlineAsm::ConstraintInfoVector CIV = IA->ParseConstraints();
345     for (unsigned i = 0, ie = CIV.size(); i < ie; ++i) {
346       InlineAsm::ConstraintInfo &C = CIV[i];
347       if (C.Type != InlineAsm::isInput)
348         for (unsigned j = 0, je = C.Codes.size(); j < je; ++j)
349           if (StringRef(C.Codes[j]).equals_lower("{ctr}"))
350             return true;
351     }
352     return false;
353   };
354 
355   // Determining the address of a TLS variable results in a function call in
356   // certain TLS models.
357   std::function<bool(const Value *)> memAddrUsesCTR =
358       [&memAddrUsesCTR, &TM, &Visited](const Value *MemAddr) -> bool {
359     // No need to traverse again if we already checked this operand.
360     if (!Visited.insert(MemAddr).second)
361       return false;
362     const auto *GV = dyn_cast<GlobalValue>(MemAddr);
363     if (!GV) {
364       // Recurse to check for constants that refer to TLS global variables.
365       if (const auto *CV = dyn_cast<Constant>(MemAddr))
366         for (const auto &CO : CV->operands())
367           if (memAddrUsesCTR(CO))
368             return true;
369 
370       return false;
371     }
372 
373     if (!GV->isThreadLocal())
374       return false;
375     TLSModel::Model Model = TM.getTLSModel(GV);
376     return Model == TLSModel::GeneralDynamic ||
377       Model == TLSModel::LocalDynamic;
378   };
379 
380   auto isLargeIntegerTy = [](bool Is32Bit, Type *Ty) {
381     if (IntegerType *ITy = dyn_cast<IntegerType>(Ty))
382       return ITy->getBitWidth() > (Is32Bit ? 32U : 64U);
383 
384     return false;
385   };
386 
387   for (BasicBlock::iterator J = BB->begin(), JE = BB->end();
388        J != JE; ++J) {
389     if (CallInst *CI = dyn_cast<CallInst>(J)) {
390       // Inline ASM is okay, unless it clobbers the ctr register.
391       if (InlineAsm *IA = dyn_cast<InlineAsm>(CI->getCalledOperand())) {
392         if (asmClobbersCTR(IA))
393           return true;
394         continue;
395       }
396 
397       if (Function *F = CI->getCalledFunction()) {
398         // Most intrinsics don't become function calls, but some might.
399         // sin, cos, exp and log are always calls.
400         unsigned Opcode = 0;
401         if (F->getIntrinsicID() != Intrinsic::not_intrinsic) {
402           switch (F->getIntrinsicID()) {
403           default: continue;
404           // If we have a call to loop_decrement or set_loop_iterations,
405           // we're definitely using CTR.
406           case Intrinsic::set_loop_iterations:
407           case Intrinsic::loop_decrement:
408             return true;
409 
410           // Binary operations on 128-bit value will use CTR.
411           case Intrinsic::experimental_constrained_fadd:
412           case Intrinsic::experimental_constrained_fsub:
413           case Intrinsic::experimental_constrained_fmul:
414           case Intrinsic::experimental_constrained_fdiv:
415           case Intrinsic::experimental_constrained_frem:
416             if (F->getType()->getScalarType()->isFP128Ty() ||
417                 F->getType()->getScalarType()->isPPC_FP128Ty())
418               return true;
419             break;
420 
421           case Intrinsic::experimental_constrained_fptosi:
422           case Intrinsic::experimental_constrained_fptoui:
423           case Intrinsic::experimental_constrained_sitofp:
424           case Intrinsic::experimental_constrained_uitofp: {
425             Type *SrcType = CI->getArgOperand(0)->getType()->getScalarType();
426             Type *DstType = CI->getType()->getScalarType();
427             if (SrcType->isPPC_FP128Ty() || DstType->isPPC_FP128Ty() ||
428                 isLargeIntegerTy(!TM.isPPC64(), SrcType) ||
429                 isLargeIntegerTy(!TM.isPPC64(), DstType))
430               return true;
431             break;
432           }
433 
434           // Exclude eh_sjlj_setjmp; we don't need to exclude eh_sjlj_longjmp
435           // because, although it does clobber the counter register, the
436           // control can't then return to inside the loop unless there is also
437           // an eh_sjlj_setjmp.
438           case Intrinsic::eh_sjlj_setjmp:
439 
440           case Intrinsic::memcpy:
441           case Intrinsic::memmove:
442           case Intrinsic::memset:
443           case Intrinsic::powi:
444           case Intrinsic::log:
445           case Intrinsic::log2:
446           case Intrinsic::log10:
447           case Intrinsic::exp:
448           case Intrinsic::exp2:
449           case Intrinsic::pow:
450           case Intrinsic::sin:
451           case Intrinsic::cos:
452           case Intrinsic::experimental_constrained_powi:
453           case Intrinsic::experimental_constrained_log:
454           case Intrinsic::experimental_constrained_log2:
455           case Intrinsic::experimental_constrained_log10:
456           case Intrinsic::experimental_constrained_exp:
457           case Intrinsic::experimental_constrained_exp2:
458           case Intrinsic::experimental_constrained_pow:
459           case Intrinsic::experimental_constrained_sin:
460           case Intrinsic::experimental_constrained_cos:
461             return true;
462           case Intrinsic::copysign:
463             if (CI->getArgOperand(0)->getType()->getScalarType()->
464                 isPPC_FP128Ty())
465               return true;
466             else
467               continue; // ISD::FCOPYSIGN is never a library call.
468           case Intrinsic::fma:                Opcode = ISD::FMA;        break;
469           case Intrinsic::sqrt:               Opcode = ISD::FSQRT;      break;
470           case Intrinsic::floor:              Opcode = ISD::FFLOOR;     break;
471           case Intrinsic::ceil:               Opcode = ISD::FCEIL;      break;
472           case Intrinsic::trunc:              Opcode = ISD::FTRUNC;     break;
473           case Intrinsic::rint:               Opcode = ISD::FRINT;      break;
474           case Intrinsic::lrint:              Opcode = ISD::LRINT;      break;
475           case Intrinsic::llrint:             Opcode = ISD::LLRINT;     break;
476           case Intrinsic::nearbyint:          Opcode = ISD::FNEARBYINT; break;
477           case Intrinsic::round:              Opcode = ISD::FROUND;     break;
478           case Intrinsic::lround:             Opcode = ISD::LROUND;     break;
479           case Intrinsic::llround:            Opcode = ISD::LLROUND;    break;
480           case Intrinsic::minnum:             Opcode = ISD::FMINNUM;    break;
481           case Intrinsic::maxnum:             Opcode = ISD::FMAXNUM;    break;
482           case Intrinsic::experimental_constrained_fcmp:
483             Opcode = ISD::STRICT_FSETCC;
484             break;
485           case Intrinsic::experimental_constrained_fcmps:
486             Opcode = ISD::STRICT_FSETCCS;
487             break;
488           case Intrinsic::experimental_constrained_fma:
489             Opcode = ISD::STRICT_FMA;
490             break;
491           case Intrinsic::experimental_constrained_sqrt:
492             Opcode = ISD::STRICT_FSQRT;
493             break;
494           case Intrinsic::experimental_constrained_floor:
495             Opcode = ISD::STRICT_FFLOOR;
496             break;
497           case Intrinsic::experimental_constrained_ceil:
498             Opcode = ISD::STRICT_FCEIL;
499             break;
500           case Intrinsic::experimental_constrained_trunc:
501             Opcode = ISD::STRICT_FTRUNC;
502             break;
503           case Intrinsic::experimental_constrained_rint:
504             Opcode = ISD::STRICT_FRINT;
505             break;
506           case Intrinsic::experimental_constrained_lrint:
507             Opcode = ISD::STRICT_LRINT;
508             break;
509           case Intrinsic::experimental_constrained_llrint:
510             Opcode = ISD::STRICT_LLRINT;
511             break;
512           case Intrinsic::experimental_constrained_nearbyint:
513             Opcode = ISD::STRICT_FNEARBYINT;
514             break;
515           case Intrinsic::experimental_constrained_round:
516             Opcode = ISD::STRICT_FROUND;
517             break;
518           case Intrinsic::experimental_constrained_lround:
519             Opcode = ISD::STRICT_LROUND;
520             break;
521           case Intrinsic::experimental_constrained_llround:
522             Opcode = ISD::STRICT_LLROUND;
523             break;
524           case Intrinsic::experimental_constrained_minnum:
525             Opcode = ISD::STRICT_FMINNUM;
526             break;
527           case Intrinsic::experimental_constrained_maxnum:
528             Opcode = ISD::STRICT_FMAXNUM;
529             break;
530           case Intrinsic::umul_with_overflow: Opcode = ISD::UMULO;      break;
531           case Intrinsic::smul_with_overflow: Opcode = ISD::SMULO;      break;
532           }
533         }
534 
535         // PowerPC does not use [US]DIVREM or other library calls for
536         // operations on regular types which are not otherwise library calls
537         // (i.e. soft float or atomics). If adapting for targets that do,
538         // additional care is required here.
539 
540         LibFunc Func;
541         if (!F->hasLocalLinkage() && F->hasName() && LibInfo &&
542             LibInfo->getLibFunc(F->getName(), Func) &&
543             LibInfo->hasOptimizedCodeGen(Func)) {
544           // Non-read-only functions are never treated as intrinsics.
545           if (!CI->onlyReadsMemory())
546             return true;
547 
548           // Conversion happens only for FP calls.
549           if (!CI->getArgOperand(0)->getType()->isFloatingPointTy())
550             return true;
551 
552           switch (Func) {
553           default: return true;
554           case LibFunc_copysign:
555           case LibFunc_copysignf:
556             continue; // ISD::FCOPYSIGN is never a library call.
557           case LibFunc_copysignl:
558             return true;
559           case LibFunc_fabs:
560           case LibFunc_fabsf:
561           case LibFunc_fabsl:
562             continue; // ISD::FABS is never a library call.
563           case LibFunc_sqrt:
564           case LibFunc_sqrtf:
565           case LibFunc_sqrtl:
566             Opcode = ISD::FSQRT; break;
567           case LibFunc_floor:
568           case LibFunc_floorf:
569           case LibFunc_floorl:
570             Opcode = ISD::FFLOOR; break;
571           case LibFunc_nearbyint:
572           case LibFunc_nearbyintf:
573           case LibFunc_nearbyintl:
574             Opcode = ISD::FNEARBYINT; break;
575           case LibFunc_ceil:
576           case LibFunc_ceilf:
577           case LibFunc_ceill:
578             Opcode = ISD::FCEIL; break;
579           case LibFunc_rint:
580           case LibFunc_rintf:
581           case LibFunc_rintl:
582             Opcode = ISD::FRINT; break;
583           case LibFunc_round:
584           case LibFunc_roundf:
585           case LibFunc_roundl:
586             Opcode = ISD::FROUND; break;
587           case LibFunc_trunc:
588           case LibFunc_truncf:
589           case LibFunc_truncl:
590             Opcode = ISD::FTRUNC; break;
591           case LibFunc_fmin:
592           case LibFunc_fminf:
593           case LibFunc_fminl:
594             Opcode = ISD::FMINNUM; break;
595           case LibFunc_fmax:
596           case LibFunc_fmaxf:
597           case LibFunc_fmaxl:
598             Opcode = ISD::FMAXNUM; break;
599           }
600         }
601 
602         if (Opcode) {
603           EVT EVTy =
604               TLI->getValueType(DL, CI->getArgOperand(0)->getType(), true);
605 
606           if (EVTy == MVT::Other)
607             return true;
608 
609           if (TLI->isOperationLegalOrCustom(Opcode, EVTy))
610             continue;
611           else if (EVTy.isVector() &&
612                    TLI->isOperationLegalOrCustom(Opcode, EVTy.getScalarType()))
613             continue;
614 
615           return true;
616         }
617       }
618 
619       return true;
620     } else if (isa<BinaryOperator>(J) &&
621                (J->getType()->getScalarType()->isFP128Ty() ||
622                 J->getType()->getScalarType()->isPPC_FP128Ty())) {
623       // Most operations on f128 or ppc_f128 values become calls.
624       return true;
625     } else if (isa<UIToFPInst>(J) || isa<SIToFPInst>(J) ||
626                isa<FPToUIInst>(J) || isa<FPToSIInst>(J)) {
627       CastInst *CI = cast<CastInst>(J);
628       if (CI->getSrcTy()->getScalarType()->isPPC_FP128Ty() ||
629           CI->getDestTy()->getScalarType()->isPPC_FP128Ty() ||
630           isLargeIntegerTy(!TM.isPPC64(), CI->getSrcTy()->getScalarType()) ||
631           isLargeIntegerTy(!TM.isPPC64(), CI->getDestTy()->getScalarType()))
632         return true;
633     } else if (isLargeIntegerTy(!TM.isPPC64(),
634                                 J->getType()->getScalarType()) &&
635                (J->getOpcode() == Instruction::UDiv ||
636                 J->getOpcode() == Instruction::SDiv ||
637                 J->getOpcode() == Instruction::URem ||
638                 J->getOpcode() == Instruction::SRem)) {
639       return true;
640     } else if (!TM.isPPC64() &&
641                isLargeIntegerTy(false, J->getType()->getScalarType()) &&
642                (J->getOpcode() == Instruction::Shl ||
643                 J->getOpcode() == Instruction::AShr ||
644                 J->getOpcode() == Instruction::LShr)) {
645       // Only on PPC32, for 128-bit integers (specifically not 64-bit
646       // integers), these might be runtime calls.
647       return true;
648     } else if (isa<IndirectBrInst>(J) || isa<InvokeInst>(J)) {
649       // On PowerPC, indirect jumps use the counter register.
650       return true;
651     } else if (SwitchInst *SI = dyn_cast<SwitchInst>(J)) {
652       if (SI->getNumCases() + 1 >= (unsigned)TLI->getMinimumJumpTableEntries())
653         return true;
654     }
655 
656     // FREM is always a call.
657     if (J->getOpcode() == Instruction::FRem)
658       return true;
659 
660     if (ST->useSoftFloat()) {
661       switch(J->getOpcode()) {
662       case Instruction::FAdd:
663       case Instruction::FSub:
664       case Instruction::FMul:
665       case Instruction::FDiv:
666       case Instruction::FPTrunc:
667       case Instruction::FPExt:
668       case Instruction::FPToUI:
669       case Instruction::FPToSI:
670       case Instruction::UIToFP:
671       case Instruction::SIToFP:
672       case Instruction::FCmp:
673         return true;
674       }
675     }
676 
677     for (Value *Operand : J->operands())
678       if (memAddrUsesCTR(Operand))
679         return true;
680   }
681 
682   return false;
683 }
684 
685 bool PPCTTIImpl::isHardwareLoopProfitable(Loop *L, ScalarEvolution &SE,
686                                           AssumptionCache &AC,
687                                           TargetLibraryInfo *LibInfo,
688                                           HardwareLoopInfo &HWLoopInfo) {
689   const PPCTargetMachine &TM = ST->getTargetMachine();
690   TargetSchedModel SchedModel;
691   SchedModel.init(ST);
692 
693   // Do not convert small short loops to CTR loop.
694   unsigned ConstTripCount = SE.getSmallConstantTripCount(L);
695   if (ConstTripCount && ConstTripCount < SmallCTRLoopThreshold) {
696     SmallPtrSet<const Value *, 32> EphValues;
697     CodeMetrics::collectEphemeralValues(L, &AC, EphValues);
698     CodeMetrics Metrics;
699     for (BasicBlock *BB : L->blocks())
700       Metrics.analyzeBasicBlock(BB, *this, EphValues);
701     // 6 is an approximate latency for the mtctr instruction.
702     if (Metrics.NumInsts <= (6 * SchedModel.getIssueWidth()))
703       return false;
704   }
705 
706   // We don't want to spill/restore the counter register, and so we don't
707   // want to use the counter register if the loop contains calls.
708   SmallPtrSet<const Value *, 4> Visited;
709   for (Loop::block_iterator I = L->block_begin(), IE = L->block_end();
710        I != IE; ++I)
711     if (mightUseCTR(*I, LibInfo, Visited))
712       return false;
713 
714   SmallVector<BasicBlock*, 4> ExitingBlocks;
715   L->getExitingBlocks(ExitingBlocks);
716 
717   // If there is an exit edge known to be frequently taken,
718   // we should not transform this loop.
719   for (auto &BB : ExitingBlocks) {
720     Instruction *TI = BB->getTerminator();
721     if (!TI) continue;
722 
723     if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
724       uint64_t TrueWeight = 0, FalseWeight = 0;
725       if (!BI->isConditional() ||
726           !BI->extractProfMetadata(TrueWeight, FalseWeight))
727         continue;
728 
729       // If the exit path is more frequent than the loop path,
730       // we return here without further analysis for this loop.
731       bool TrueIsExit = !L->contains(BI->getSuccessor(0));
732       if (( TrueIsExit && FalseWeight < TrueWeight) ||
733           (!TrueIsExit && FalseWeight > TrueWeight))
734         return false;
735     }
736   }
737 
738   LLVMContext &C = L->getHeader()->getContext();
739   HWLoopInfo.CountType = TM.isPPC64() ?
740     Type::getInt64Ty(C) : Type::getInt32Ty(C);
741   HWLoopInfo.LoopDecrement = ConstantInt::get(HWLoopInfo.CountType, 1);
742   return true;
743 }
744 
745 void PPCTTIImpl::getUnrollingPreferences(Loop *L, ScalarEvolution &SE,
746                                          TTI::UnrollingPreferences &UP) {
747   if (ST->getCPUDirective() == PPC::DIR_A2) {
748     // The A2 is in-order with a deep pipeline, and concatenation unrolling
749     // helps expose latency-hiding opportunities to the instruction scheduler.
750     UP.Partial = UP.Runtime = true;
751 
752     // We unroll a lot on the A2 (hundreds of instructions), and the benefits
753     // often outweigh the cost of a division to compute the trip count.
754     UP.AllowExpensiveTripCount = true;
755   }
756 
757   BaseT::getUnrollingPreferences(L, SE, UP);
758 }
759 
760 void PPCTTIImpl::getPeelingPreferences(Loop *L, ScalarEvolution &SE,
761                                        TTI::PeelingPreferences &PP) {
762   BaseT::getPeelingPreferences(L, SE, PP);
763 }
764 // This function returns true to allow using coldcc calling convention.
765 // Returning true results in coldcc being used for functions which are cold at
766 // all call sites when the callers of the functions are not calling any other
767 // non coldcc functions.
768 bool PPCTTIImpl::useColdCCForColdCall(Function &F) {
769   return EnablePPCColdCC;
770 }
771 
772 bool PPCTTIImpl::enableAggressiveInterleaving(bool LoopHasReductions) {
773   // On the A2, always unroll aggressively.
774   if (ST->getCPUDirective() == PPC::DIR_A2)
775     return true;
776 
777   return LoopHasReductions;
778 }
779 
780 PPCTTIImpl::TTI::MemCmpExpansionOptions
781 PPCTTIImpl::enableMemCmpExpansion(bool OptSize, bool IsZeroCmp) const {
782   TTI::MemCmpExpansionOptions Options;
783   Options.LoadSizes = {8, 4, 2, 1};
784   Options.MaxNumLoads = TLI->getMaxExpandSizeMemcmp(OptSize);
785   return Options;
786 }
787 
788 bool PPCTTIImpl::enableInterleavedAccessVectorization() {
789   return true;
790 }
791 
792 unsigned PPCTTIImpl::getNumberOfRegisters(unsigned ClassID) const {
793   assert(ClassID == GPRRC || ClassID == FPRRC ||
794          ClassID == VRRC || ClassID == VSXRC);
795   if (ST->hasVSX()) {
796     assert(ClassID == GPRRC || ClassID == VSXRC || ClassID == VRRC);
797     return ClassID == VSXRC ? 64 : 32;
798   }
799   assert(ClassID == GPRRC || ClassID == FPRRC || ClassID == VRRC);
800   return 32;
801 }
802 
803 unsigned PPCTTIImpl::getRegisterClassForType(bool Vector, Type *Ty) const {
804   if (Vector)
805     return ST->hasVSX() ? VSXRC : VRRC;
806   else if (Ty && (Ty->getScalarType()->isFloatTy() ||
807                   Ty->getScalarType()->isDoubleTy()))
808     return ST->hasVSX() ? VSXRC : FPRRC;
809   else if (Ty && (Ty->getScalarType()->isFP128Ty() ||
810                   Ty->getScalarType()->isPPC_FP128Ty()))
811     return VRRC;
812   else if (Ty && Ty->getScalarType()->isHalfTy())
813     return VSXRC;
814   else
815     return GPRRC;
816 }
817 
818 const char* PPCTTIImpl::getRegisterClassName(unsigned ClassID) const {
819 
820   switch (ClassID) {
821     default:
822       llvm_unreachable("unknown register class");
823       return "PPC::unknown register class";
824     case GPRRC:       return "PPC::GPRRC";
825     case FPRRC:       return "PPC::FPRRC";
826     case VRRC:        return "PPC::VRRC";
827     case VSXRC:       return "PPC::VSXRC";
828   }
829 }
830 
831 unsigned PPCTTIImpl::getRegisterBitWidth(bool Vector) const {
832   if (Vector) {
833     if (ST->hasAltivec()) return 128;
834     return 0;
835   }
836 
837   if (ST->isPPC64())
838     return 64;
839   return 32;
840 
841 }
842 
843 unsigned PPCTTIImpl::getCacheLineSize() const {
844   // Check first if the user specified a custom line size.
845   if (CacheLineSize.getNumOccurrences() > 0)
846     return CacheLineSize;
847 
848   // Starting with P7 we have a cache line size of 128.
849   unsigned Directive = ST->getCPUDirective();
850   // Assume that Future CPU has the same cache line size as the others.
851   if (Directive == PPC::DIR_PWR7 || Directive == PPC::DIR_PWR8 ||
852       Directive == PPC::DIR_PWR9 || Directive == PPC::DIR_PWR10 ||
853       Directive == PPC::DIR_PWR_FUTURE)
854     return 128;
855 
856   // On other processors return a default of 64 bytes.
857   return 64;
858 }
859 
860 unsigned PPCTTIImpl::getPrefetchDistance() const {
861   return 300;
862 }
863 
864 unsigned PPCTTIImpl::getMaxInterleaveFactor(unsigned VF) {
865   unsigned Directive = ST->getCPUDirective();
866   // The 440 has no SIMD support, but floating-point instructions
867   // have a 5-cycle latency, so unroll by 5x for latency hiding.
868   if (Directive == PPC::DIR_440)
869     return 5;
870 
871   // The A2 has no SIMD support, but floating-point instructions
872   // have a 6-cycle latency, so unroll by 6x for latency hiding.
873   if (Directive == PPC::DIR_A2)
874     return 6;
875 
876   // FIXME: For lack of any better information, do no harm...
877   if (Directive == PPC::DIR_E500mc || Directive == PPC::DIR_E5500)
878     return 1;
879 
880   // For P7 and P8, floating-point instructions have a 6-cycle latency and
881   // there are two execution units, so unroll by 12x for latency hiding.
882   // FIXME: the same for P9 as previous gen until POWER9 scheduling is ready
883   // FIXME: the same for P10 as previous gen until POWER10 scheduling is ready
884   // Assume that future is the same as the others.
885   if (Directive == PPC::DIR_PWR7 || Directive == PPC::DIR_PWR8 ||
886       Directive == PPC::DIR_PWR9 || Directive == PPC::DIR_PWR10 ||
887       Directive == PPC::DIR_PWR_FUTURE)
888     return 12;
889 
890   // For most things, modern systems have two execution units (and
891   // out-of-order execution).
892   return 2;
893 }
894 
895 // Adjust the cost of vector instructions on targets which there is overlap
896 // between the vector and scalar units, thereby reducing the overall throughput
897 // of vector code wrt. scalar code.
898 int PPCTTIImpl::vectorCostAdjustment(int Cost, unsigned Opcode, Type *Ty1,
899                                      Type *Ty2) {
900   if (!ST->vectorsUseTwoUnits() || !Ty1->isVectorTy())
901     return Cost;
902 
903   std::pair<int, MVT> LT1 = TLI->getTypeLegalizationCost(DL, Ty1);
904   // If type legalization involves splitting the vector, we don't want to
905   // double the cost at every step - only the last step.
906   if (LT1.first != 1 || !LT1.second.isVector())
907     return Cost;
908 
909   int ISD = TLI->InstructionOpcodeToISD(Opcode);
910   if (TLI->isOperationExpand(ISD, LT1.second))
911     return Cost;
912 
913   if (Ty2) {
914     std::pair<int, MVT> LT2 = TLI->getTypeLegalizationCost(DL, Ty2);
915     if (LT2.first != 1 || !LT2.second.isVector())
916       return Cost;
917   }
918 
919   return Cost * 2;
920 }
921 
922 int PPCTTIImpl::getArithmeticInstrCost(unsigned Opcode, Type *Ty,
923                                        TTI::TargetCostKind CostKind,
924                                        TTI::OperandValueKind Op1Info,
925                                        TTI::OperandValueKind Op2Info,
926                                        TTI::OperandValueProperties Opd1PropInfo,
927                                        TTI::OperandValueProperties Opd2PropInfo,
928                                        ArrayRef<const Value *> Args,
929                                        const Instruction *CxtI) {
930   assert(TLI->InstructionOpcodeToISD(Opcode) && "Invalid opcode");
931   // TODO: Handle more cost kinds.
932   if (CostKind != TTI::TCK_RecipThroughput)
933     return BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info,
934                                          Op2Info, Opd1PropInfo,
935                                          Opd2PropInfo, Args, CxtI);
936 
937   // Fallback to the default implementation.
938   int Cost = BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info,
939                                            Op2Info,
940                                            Opd1PropInfo, Opd2PropInfo);
941   return vectorCostAdjustment(Cost, Opcode, Ty, nullptr);
942 }
943 
944 int PPCTTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
945                                Type *SubTp) {
946   // Legalize the type.
947   std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, Tp);
948 
949   // PPC, for both Altivec/VSX, support cheap arbitrary permutations
950   // (at least in the sense that there need only be one non-loop-invariant
951   // instruction). We need one such shuffle instruction for each actual
952   // register (this is not true for arbitrary shuffles, but is true for the
953   // structured types of shuffles covered by TTI::ShuffleKind).
954   return vectorCostAdjustment(LT.first, Instruction::ShuffleVector, Tp,
955                               nullptr);
956 }
957 
958 int PPCTTIImpl::getCFInstrCost(unsigned Opcode, TTI::TargetCostKind CostKind) {
959   if (CostKind != TTI::TCK_RecipThroughput)
960     return Opcode == Instruction::PHI ? 0 : 1;
961   // Branches are assumed to be predicted.
962   return CostKind == TTI::TCK_RecipThroughput ? 0 : 1;
963 }
964 
965 int PPCTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src,
966                                  TTI::CastContextHint CCH,
967                                  TTI::TargetCostKind CostKind,
968                                  const Instruction *I) {
969   assert(TLI->InstructionOpcodeToISD(Opcode) && "Invalid opcode");
970 
971   int Cost = BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I);
972   Cost = vectorCostAdjustment(Cost, Opcode, Dst, Src);
973   // TODO: Allow non-throughput costs that aren't binary.
974   if (CostKind != TTI::TCK_RecipThroughput)
975     return Cost == 0 ? 0 : 1;
976   return Cost;
977 }
978 
979 int PPCTTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy,
980                                    TTI::TargetCostKind CostKind,
981                                    const Instruction *I) {
982   int Cost = BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, CostKind, I);
983   // TODO: Handle other cost kinds.
984   if (CostKind != TTI::TCK_RecipThroughput)
985     return Cost;
986   return vectorCostAdjustment(Cost, Opcode, ValTy, nullptr);
987 }
988 
989 int PPCTTIImpl::getVectorInstrCost(unsigned Opcode, Type *Val, unsigned Index) {
990   assert(Val->isVectorTy() && "This must be a vector type");
991 
992   int ISD = TLI->InstructionOpcodeToISD(Opcode);
993   assert(ISD && "Invalid opcode");
994 
995   int Cost = BaseT::getVectorInstrCost(Opcode, Val, Index);
996   Cost = vectorCostAdjustment(Cost, Opcode, Val, nullptr);
997 
998   if (ST->hasVSX() && Val->getScalarType()->isDoubleTy()) {
999     // Double-precision scalars are already located in index #0 (or #1 if LE).
1000     if (ISD == ISD::EXTRACT_VECTOR_ELT &&
1001         Index == (ST->isLittleEndian() ? 1 : 0))
1002       return 0;
1003 
1004     return Cost;
1005 
1006   } else if (Val->getScalarType()->isIntegerTy() && Index != -1U) {
1007     if (ST->hasP9Altivec()) {
1008       if (ISD == ISD::INSERT_VECTOR_ELT)
1009         // A move-to VSR and a permute/insert.  Assume vector operation cost
1010         // for both (cost will be 2x on P9).
1011         return vectorCostAdjustment(2, Opcode, Val, nullptr);
1012 
1013       // It's an extract.  Maybe we can do a cheap move-from VSR.
1014       unsigned EltSize = Val->getScalarSizeInBits();
1015       if (EltSize == 64) {
1016         unsigned MfvsrdIndex = ST->isLittleEndian() ? 1 : 0;
1017         if (Index == MfvsrdIndex)
1018           return 1;
1019       } else if (EltSize == 32) {
1020         unsigned MfvsrwzIndex = ST->isLittleEndian() ? 2 : 1;
1021         if (Index == MfvsrwzIndex)
1022           return 1;
1023       }
1024 
1025       // We need a vector extract (or mfvsrld).  Assume vector operation cost.
1026       // The cost of the load constant for a vector extract is disregarded
1027       // (invariant, easily schedulable).
1028       return vectorCostAdjustment(1, Opcode, Val, nullptr);
1029 
1030     } else if (ST->hasDirectMove())
1031       // Assume permute has standard cost.
1032       // Assume move-to/move-from VSR have 2x standard cost.
1033       return 3;
1034   }
1035 
1036   // Estimated cost of a load-hit-store delay.  This was obtained
1037   // experimentally as a minimum needed to prevent unprofitable
1038   // vectorization for the paq8p benchmark.  It may need to be
1039   // raised further if other unprofitable cases remain.
1040   unsigned LHSPenalty = 2;
1041   if (ISD == ISD::INSERT_VECTOR_ELT)
1042     LHSPenalty += 7;
1043 
1044   // Vector element insert/extract with Altivec is very expensive,
1045   // because they require store and reload with the attendant
1046   // processor stall for load-hit-store.  Until VSX is available,
1047   // these need to be estimated as very costly.
1048   if (ISD == ISD::EXTRACT_VECTOR_ELT ||
1049       ISD == ISD::INSERT_VECTOR_ELT)
1050     return LHSPenalty + Cost;
1051 
1052   return Cost;
1053 }
1054 
1055 int PPCTTIImpl::getMemoryOpCost(unsigned Opcode, Type *Src,
1056                                 MaybeAlign Alignment, unsigned AddressSpace,
1057                                 TTI::TargetCostKind CostKind,
1058                                 const Instruction *I) {
1059   if (TLI->getValueType(DL, Src,  true) == MVT::Other)
1060     return BaseT::getMemoryOpCost(Opcode, Src, Alignment, AddressSpace,
1061                                   CostKind);
1062   // Legalize the type.
1063   std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, Src);
1064   assert((Opcode == Instruction::Load || Opcode == Instruction::Store) &&
1065          "Invalid Opcode");
1066 
1067   int Cost = BaseT::getMemoryOpCost(Opcode, Src, Alignment, AddressSpace,
1068                                     CostKind);
1069   // TODO: Handle other cost kinds.
1070   if (CostKind != TTI::TCK_RecipThroughput)
1071     return Cost;
1072 
1073   Cost = vectorCostAdjustment(Cost, Opcode, Src, nullptr);
1074 
1075   bool IsAltivecType = ST->hasAltivec() &&
1076                        (LT.second == MVT::v16i8 || LT.second == MVT::v8i16 ||
1077                         LT.second == MVT::v4i32 || LT.second == MVT::v4f32);
1078   bool IsVSXType = ST->hasVSX() &&
1079                    (LT.second == MVT::v2f64 || LT.second == MVT::v2i64);
1080 
1081   // VSX has 32b/64b load instructions. Legalization can handle loading of
1082   // 32b/64b to VSR correctly and cheaply. But BaseT::getMemoryOpCost and
1083   // PPCTargetLowering can't compute the cost appropriately. So here we
1084   // explicitly check this case.
1085   unsigned MemBytes = Src->getPrimitiveSizeInBits();
1086   if (Opcode == Instruction::Load && ST->hasVSX() && IsAltivecType &&
1087       (MemBytes == 64 || (ST->hasP8Vector() && MemBytes == 32)))
1088     return 1;
1089 
1090   // Aligned loads and stores are easy.
1091   unsigned SrcBytes = LT.second.getStoreSize();
1092   if (!SrcBytes || !Alignment || *Alignment >= SrcBytes)
1093     return Cost;
1094 
1095   // If we can use the permutation-based load sequence, then this is also
1096   // relatively cheap (not counting loop-invariant instructions): one load plus
1097   // one permute (the last load in a series has extra cost, but we're
1098   // neglecting that here). Note that on the P7, we could do unaligned loads
1099   // for Altivec types using the VSX instructions, but that's more expensive
1100   // than using the permutation-based load sequence. On the P8, that's no
1101   // longer true.
1102   if (Opcode == Instruction::Load && (!ST->hasP8Vector() && IsAltivecType) &&
1103       *Alignment >= LT.second.getScalarType().getStoreSize())
1104     return Cost + LT.first; // Add the cost of the permutations.
1105 
1106   // For VSX, we can do unaligned loads and stores on Altivec/VSX types. On the
1107   // P7, unaligned vector loads are more expensive than the permutation-based
1108   // load sequence, so that might be used instead, but regardless, the net cost
1109   // is about the same (not counting loop-invariant instructions).
1110   if (IsVSXType || (ST->hasVSX() && IsAltivecType))
1111     return Cost;
1112 
1113   // Newer PPC supports unaligned memory access.
1114   if (TLI->allowsMisalignedMemoryAccesses(LT.second, 0))
1115     return Cost;
1116 
1117   // PPC in general does not support unaligned loads and stores. They'll need
1118   // to be decomposed based on the alignment factor.
1119 
1120   // Add the cost of each scalar load or store.
1121   assert(Alignment);
1122   Cost += LT.first * ((SrcBytes / Alignment->value()) - 1);
1123 
1124   // For a vector type, there is also scalarization overhead (only for
1125   // stores, loads are expanded using the vector-load + permutation sequence,
1126   // which is much less expensive).
1127   if (Src->isVectorTy() && Opcode == Instruction::Store)
1128     for (int i = 0, e = cast<FixedVectorType>(Src)->getNumElements(); i < e;
1129          ++i)
1130       Cost += getVectorInstrCost(Instruction::ExtractElement, Src, i);
1131 
1132   return Cost;
1133 }
1134 
1135 int PPCTTIImpl::getInterleavedMemoryOpCost(
1136     unsigned Opcode, Type *VecTy, unsigned Factor, ArrayRef<unsigned> Indices,
1137     Align Alignment, unsigned AddressSpace, TTI::TargetCostKind CostKind,
1138     bool UseMaskForCond, bool UseMaskForGaps) {
1139   if (UseMaskForCond || UseMaskForGaps)
1140     return BaseT::getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices,
1141                                              Alignment, AddressSpace, CostKind,
1142                                              UseMaskForCond, UseMaskForGaps);
1143 
1144   assert(isa<VectorType>(VecTy) &&
1145          "Expect a vector type for interleaved memory op");
1146 
1147   // Legalize the type.
1148   std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, VecTy);
1149 
1150   // Firstly, the cost of load/store operation.
1151   int Cost =
1152       getMemoryOpCost(Opcode, VecTy, MaybeAlign(Alignment), AddressSpace,
1153                       CostKind);
1154 
1155   // PPC, for both Altivec/VSX, support cheap arbitrary permutations
1156   // (at least in the sense that there need only be one non-loop-invariant
1157   // instruction). For each result vector, we need one shuffle per incoming
1158   // vector (except that the first shuffle can take two incoming vectors
1159   // because it does not need to take itself).
1160   Cost += Factor*(LT.first-1);
1161 
1162   return Cost;
1163 }
1164 
1165 unsigned PPCTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
1166                                            TTI::TargetCostKind CostKind) {
1167   return BaseT::getIntrinsicInstrCost(ICA, CostKind);
1168 }
1169 
1170 bool PPCTTIImpl::canSaveCmp(Loop *L, BranchInst **BI, ScalarEvolution *SE,
1171                             LoopInfo *LI, DominatorTree *DT,
1172                             AssumptionCache *AC, TargetLibraryInfo *LibInfo) {
1173   // Process nested loops first.
1174   for (Loop::iterator I = L->begin(), E = L->end(); I != E; ++I)
1175     if (canSaveCmp(*I, BI, SE, LI, DT, AC, LibInfo))
1176       return false; // Stop search.
1177 
1178   HardwareLoopInfo HWLoopInfo(L);
1179 
1180   if (!HWLoopInfo.canAnalyze(*LI))
1181     return false;
1182 
1183   if (!isHardwareLoopProfitable(L, *SE, *AC, LibInfo, HWLoopInfo))
1184     return false;
1185 
1186   if (!HWLoopInfo.isHardwareLoopCandidate(*SE, *LI, *DT))
1187     return false;
1188 
1189   *BI = HWLoopInfo.ExitBranch;
1190   return true;
1191 }
1192 
1193 bool PPCTTIImpl::isLSRCostLess(TargetTransformInfo::LSRCost &C1,
1194                                TargetTransformInfo::LSRCost &C2) {
1195   // PowerPC default behaviour here is "instruction number 1st priority".
1196   // If LsrNoInsnsCost is set, call default implementation.
1197   if (!LsrNoInsnsCost)
1198     return std::tie(C1.Insns, C1.NumRegs, C1.AddRecCost, C1.NumIVMuls,
1199                     C1.NumBaseAdds, C1.ScaleCost, C1.ImmCost, C1.SetupCost) <
1200            std::tie(C2.Insns, C2.NumRegs, C2.AddRecCost, C2.NumIVMuls,
1201                     C2.NumBaseAdds, C2.ScaleCost, C2.ImmCost, C2.SetupCost);
1202   else
1203     return TargetTransformInfoImplBase::isLSRCostLess(C1, C2);
1204 }
1205